Yarns, fabrics, and garments including lignin as a primary dye agent and methods of dyeing textiles with lignin

ABSTRACT

A yarn, fabric, or garment that includes a plurality of fibers or a fiber-based material. The yarn, fabric, or garment includes lignin as a primary dye agent. Lignin may be present in the plurality of fibers or the fiber-based material in a range of 0.3 percent to 10 percent by weight.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 17/126,169, filed Dec. 18, 2020, which claims the benefit of, and priority to, U.S. Provisional Patent Application Ser. No. 62/988,980, filed Mar. 13, 2020. The entire contents of each of the above applications are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to dyeing of textiles and, more specifically, to utilizing lignin as a dye stuff to dye textiles.

DISCUSSION OF RELATED ART

Lignin is a byproduct of the paper industry, bio-fuel industry, and the echo-chemical industries including cosmetics, pharmaceuticals, etc. These industries utilize the core of trees that are grown in sustainable forests to harvest cellulose and hemi-cellulose to provide raw materials. When the core of the trees is harvested, the outer bark of the trees is typically considered waste. Lignin is found in the outer bark and is the second most abundant polymer from biomass after cellulose. For example, large quantities of lignin are available as a byproduct from the pulping and paper industries. For example, less than two percent of the lignin is recovered for utilization as a chemical product with the remainder being considered waste.

Primarily lignin is used for forming a precursor for forming paper, lignocellulose. Lignocellulose is one third lignin by mass. Lignin can be procured from a variety of trees including, but not limited to, birchwood, eucalyptus, and pine.

SUMMARY

This disclosure relates generally to a dyestuff including lignin as a colorant to dye fibers for use in textiles and methods for using the dyestuff to dye fibers, yarns, textiles, or garments.

In an aspect of the present disclosure, a dye bath includes an aqueous solution including lignin in a range of 10 percent to 30 percent by weight of the aqueous solution.

In another aspect of the present disclosure, a method of dyeing a fabric including preparing a first dye bath including an aqueous solution having lignin in a range of 10 percent to 30 percent by weight of the aqueous solution and passing a fabric through the first dye bath such that the fabric pics up lignin to dye the fabric.

In another aspect of the present disclosure, a method of dyeing fabric includes preparing a first dye bath comprising an aqueous solution that has lignin in a range of 10 percent to 30 percent by weight of the aqueous solution and passing a fabric through the first dye bath such that the fabric picks up lignin to dye the fabric.

In some aspects, the method includes preparing a second dye bath that includes binders or softeners and passing the dyed fabric through the second dye bath. The method may include drying the dyed fabric after passing the dyed fabric through the second ye bath.

In some aspects, passing the fabric through the first dye bath includes multiple dips of the fabric through the first dye bath. Passing the fabric through the first dye bath picks up a range of 90 percent to 100 percent by weight of lignin in the aqueous solution. The method may include drying the dyed fabric.

In certain aspects, the method includes preparing the fabric for dying before passing the fabric through the first dye bath. Preparing the fabric for dying may include washing the fabric to remove sizing or other impurities from the fabric, pre-treating the fabric with a cationic pre-treatment, selecting a cationic cotton for the fabric, or pre-treating the fabric with an anionic pre0treatment.

In another aspect of the present disclosure, a dye bath includes an aqueous solution comprising lignin in a range of 10 percent to 30 percent by weight of the aqueous solution.

In aspects, the dye bath includes wetting agents or surfactants in a range of 1 percent to 3 percent by weight of the aqueous solution. The aqueous solution may include binders up to 10 percent by weight of the aqueous solution. The aqueous solution may include softeners in a range of 1 percent to 3 percent by weight of the aqueous solution.

In some aspects, the dye bath is configured to dye a cellulosic fiber. For example, the dye bath may be configured to dye cellulosic fibers, a yarn having cellulosic fibers, a fabric having cellulosic fibers, or a garment having cellulosic fibers. The dye bath may be configured to dye fabrics having at least 40 percent cellulosic content.

In another aspect of the present disclosure, a dye bath includes an aqueous solution comprising lignin in a range of 10 percent to 30 percent by weight and binders up to 10 percent by weight. The aqueous solution being configured to dye cellulosic fibers for use in textiles.

In aspects, the aqueous solution may include wetting agents or surfactants in a range of 1 percent to 3 percent by weight of the aqueous solution. The aqueous solution may include softeners in a range of 1 percent to 3 percent by weight of the aqueous solution. The aqueous solution may be configured to dye cellulosic fibers in a fiber form, a yarn, a fabric, or a garment.

In another aspect of the present disclosure, a yarn includes a plurality of fibers comprising lignin as a primary dye agent.

In some aspects, the plurality of fibers may include lignin in a range of 0.3 percent to 10 percent by weight. The plurality of fibers may include lignin in a range of 0.3 percent to 5 percent by weight. The plurality of fibers may include at least 30 percent cellulosic fibers. The plurality of fibers may include at least 30 percent cellulosic fibers. The plurality of fibers may be bacteriostatic.

In another aspect of the present disclosure, a textile fabric includes a plurality of yarns including lignin as a primary dye agent.

In another aspect of the present disclosure, a garment includes a plurality of yarns including lignin as a primary dye agent.

In another aspect of the present disclosure, a textile fabric includes a fiber-based material including lignin as a primary dye agent.

In some aspects, the fiber-based material may include lignin in a range from 0.3 percent to 10 percent by weight. The fiber-based material may include lignin in a range from 0.3 percent to 5 percent by weight. The fiber-based material may include at least 30% cellulosic fibers. The fiber-based material may be bacteriostatic.

In some aspects, the fiber-based material may include a first fiber-based yarn and a second fiber-based yarn. The first fiber-based yarn may include lignin as a primary dye agent. The first fiber-based yarn may be a warp yarn or a weft yarn including lignin and the second fiber-based yarn is the other of the warp yarn or weft yarn. The first fiber-based yarn and the second fiber-based yarn may be woven in a twill pattern. The second fiber-based yarn may include lignin as a primary dye agent.

In another aspect of the present disclosure, a brown colored garment includes a fiber-based material including lignin as a primary dye agent.

In some aspects, the fiber-based material may include lignin in a range of 0.3 percent to 10 percent by weight. The fiber-based material may include lignin in a range of 0.3 percent to 5 percent by weight. The fiber-based material may be at least 30 percent cellulosic fibers. The fiber-based material may include a first-fiber yarn and a second yarn. The first fiber-based yarn may include lignin as a primary dye agent.

Further, to the extent consistent, any of the embodiments or aspects described herein may be used in conjunction with any or all of the other embodiments or aspects described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described hereinbelow with reference to the drawings, which are incorporated in and constitute a part of this specification, wherein:

FIG. 1 is a flowchart of a method according to an embodiment of the present disclosure; and

FIG. 2 is a flowchart of another method according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

The present disclosure will now be described more fully hereinafter with reference to example embodiments thereof with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. These example embodiments are described so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Features from one embodiment or aspect can be combined with features from any other embodiment or aspect in any appropriate combination. For example, any individual or collective features of method aspects or embodiments can be applied to apparatus, product, or component aspects or embodiments and vice versa. The disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. As used in the specification and the appended claims, the singular forms “a,” “an,” “the,” and the like include plural referents unless the context clearly dictates otherwise. In addition, while reference may be made herein to quantitative measures, values, geometric relationships or the like, unless otherwise stated, any one or more if not all of these may be absolute or approximate to account for acceptable variations that may occur, such as those due to manufacturing or engineering tolerances or the like.

This disclosure is directed to utilizing lignin as a dyestuff to dye fibers, yarns, fabrics, or garments. In some embodiments, this disclosure is directed to utilizing lignin as a dyestuff to dye cellulosic fibers, e.g., cotton fibers, hemp, and regenerated cellulosic fibers. Regenerated cellulosic fibers include, but are not limited to, lyocell, modal, and kapok.

In the textile industry lignin has been used as dye dispersant. However, lignin has not been used in a colorant or as a dyestuff. Lignin represents a component of renewable natural material that is available in sufficient quantity and is not in direct competition with food production like other natural dyes. Suitable lignin may be available from Renmatix, Stora Enso, and others.

Lignin also has inherent properties that are desired for textiles. For example, during the life of a tree, lignin in the outer bark protects the core of the tree from bacteria and fungus and has a natural brown color. When a fiber is dyed with lignin, the fiber is dyed a shade of brown and may acquire properties of lignin such that the fiber is rendered bacteriostatic and/or anti-fungal from the lignin. As disclosed herein, a fabric dyed with lignin may be rendered bacteriostatic and/or anti-fungal.

The methods detailed below have been tested on a lab scale to produce lignin dyed cotton fabrics in various shades of brown. These lignin dyed cotton fabrics have been tested to have good wash fastness for at least ten home launderings. Trials were run with natural cotton rich fabrics and bleached cotton rich fabrics. In some of the trials, the cotton rich fabrics were desized before being dyed. While the methods and results detailed herein are described with cotton fibers, this should not be seen as limiting as similar results are anticipated with other cellulosic fibers including, but not limited to, cellulosic fibers such as wool, linen, hemp, other bast fibers, rayon, viscose fibers, other manufactured cellulosic fibers, recycled cellulosic fibers, and fibers from agricultural waste having cellulosic content. The fabric may have a cellulosic content of at least 40 percent.

With reference to FIG. 1 , a method of dyeing a fabric with lignin as a dyestuff is described with respect to an embodiment of the present disclosure and is generally referred to as method 100. The method 100 includes preparing a dye bath including lignin as a dyestuff (Step 110). To prepare the dye bath, lignin powder is dissolved in a medium, e.g., water, to form a lignin solution. When water is the medium, the lignin solution is in an aqueous solution. In embodiments, lignin powder is dissolved in hot water to form a lignin solution. It will be appreciated that lignin easily dissolves in hot water such that medium-high speed stirring is sufficient to dissolve lignin in hot water. The medium-high speed stirring may be in a range of 200 rpm to 1000 rpm. In other embodiments it may be preferred to dissolve lignin powder in cold water. For example, other components of the dye bath may be prematurely activated in a hot water. To dissolve lignin in cold water, high speed stirring in a range of 500 rpm to 1000 rpm may be used to dissolve lignin in cold water. In other embodiments, lignin powder may be dissolved in cold water by high speed blending. For the purposes of this disclosure, cold water is water with a temperature less than 70° F. (21° C.) and hot water is water with a temperature greater than 122° F. (50° C.).

With the lignin in solution, the dye bath is prepared by mixing the lignin solution with one or more other components including, but not limited to, wetting agents, surfactants, binders, and softeners. In some embodiments, lignin may be added or dissolved in the dye bath simultaneously with other components, before other components, or after the other components. In an exemplary dye bath, a lignin powder in solution accounts for 10 percent to 30 percent, wetting agents and surfactants account for 1 percent to 3 percent, binders account for up to 10 percent, and softeners account for 1 percent to 3 percent of the dye bath by weight. The remainder of the dye bath may be water or other liquids. The dye bath may be formed by dissolving all the components in a liquid sequentially or simultaneously. For example, the lignin powder, wetting agents, surfactants, binder, or softeners may be added to a vat while a medium, e.g., water, in the vat is agitated until all components of the dye bath are dissolved or suspended in the dye bath.

With the dye bath formed, fabric may be padder dyed by passing the fabric through the dye bath such that the lignin in the dye bath is picked up by the fabric (Step 120). The fabric may be passed through the dye bath in a single dip or multiple dips. In trials of cold pad dyeing, pickup of the lignin from the dye bath was in a range of 90 percent to 100 percent by weight in each of the trial.

After the fabric is passed through the dye bath, the fabric is dried (Step 130). The fabric may be dried with steam. Additionally or alternatively, the dyed fabric may be dried with dry heat.

With reference to FIG. 2 , another method of dyeing a fabric with lignin as a dyestuff is described with respect to an embodiment of the present disclosure and is generally referred to as method 200. The method 200 may include a first dye bath and a second dye bath. The first dye bath may include a lignin solution, wetting agents, and/or surfactants such that the first dye bath includes the colorant or dye, e.g., lignin. The second dye bath may include binders and/or softeners such that the second dye bath includes fixatives. The method 200 includes preparing the first dye bath including lignin as a dyestuff (Step 210) and preparing the second day bath including fixatives (Step 215). The first and second dye baths may be prepared in a manner similar to preparing the dye bath as detailed above with respect to method 100.

With first and second dye baths prepared, a fabric may be padder dyed by passing the fabric through the first dye bath (Step 220) and then passing the fabric through the second dye bath (Step 225). As the fabric passes through the first dye bath, the lignin in the first dye bath is picked up by the fabric. The fabric may be passed through the first dye bath in a single dip or multiple dips. Similarly, the fabric may be passed through the second dye bath in a single dip or multiple dips. In trials of cold pad dyeing, pickup of the lignin from the first dye bath was in a range of 90 percent to 100 percent by weight in each of the trials.

After the fabric is passed through the dye bath, the fabric is dried (Step 230). The fabric may be dried with steam. Additionally or alternatively, the dyed fabric may be dried with dry heat.

The methods 100, 200 detailed above may include pretreating the fabric before the fabric is passed through the dye bath. For example, the fabric may be prepared without removing any impurities, the fabric may be washed to remove sizing or other impurities, the fabric may be treated with a cationic or anionic pretreatment, or cationic cotton may be selected. The pretreating of the fabric may improve the consistency of the dyeing process. The pretreating of the fabric may improve the dye pickup and/or other properties of the dyed fabric including color fastness.

The methods 100, 200 detailed above may be used as a batch dyeing process or may be used as a continuous dyeing process. While the dyeing steps detailed above, e.g., Steps 120, 220, 225, are described with respect to fabric padder dyeing, other dyeing processes may be used including, but not limited to, fiber dyeing by stock dyeing or dope dyeing; yarn dyeing by skein dyeing, package dyeing, or beam dyeing; piece dyeing fabric; and garment dyeing.

Examples of suitable wetting agents and surfactants are Ultravon®, Invadine®, or Invalon® each available from Huntsman International LLC. Examples of suitable binders are acrylic, polyurethane binders from earth pigments, Resimax available from Montega Chemical Solutions. Examples of suitable softeners are silicon softeners such as NE 810 available from Wacker Chemicals, DICRYLAN® available form Huntsman International LLC, or Cepreton®.

In accordance with another aspect of the present disclosure, a fabric dyed with lignin as the primary dye agent is described. The fabric may be any type of textile fabric suitable for garments and accessories. Accordingly, the fabric can be a woven fabric, knit fabric, a nonwoven fabric, a laminate, and/or any combination thereof. The lignin-dyed fabric itself may be dyed with lignin in the processes described above. The lignin-dyed fabric may also be constructed of lignin-dyed yarns. In one example, the fabric is a woven fabric having a plurality of warp yarns and a plurality of weft yarns interwoven with the plurality of warp yarns to define the woven fabric with at least one of the warp or weft yarns is dyed with lignin. In such examples, the lignin-dyed yarns are dyed in yarn form.

As used herein, the term “yarn” should be understood as meaning a length of interlocked textile fibers or filaments that is suitable for the production of fabrics. In some embodiments, lignin dyeing is performed on yarn or ropes of yarn. In other embodiments, the yarn is converted to packages, which can be used in weaving or knitting operations. For example, lignin-dyed yarn may be weaved into a twill fabric such as a denim fabric, and in some examples, this dyed yarn is then used as the warp yarn in a twill fabric weave. However, it is to be appreciated that both the warp and weft yarns may be lignin dyed as described above. Accordingly, unless specified, the term yarn should be understood herein as inclusively referring to any of individual yarns, ropes of yarn, packages of yarn, sheets of yarn, and yarn that is present in a fabric.

The fabric when woven or knit can be formed from any number of yarn types, such as a spun yarn or continuous filament yarn. Spun yarn may include natural fibers, synthetic fibers, or blends of natural and synthetic fibers. Natural fibers include cellulosic fibers such as cotton, bamboo, flax, hemp, or others and protein fibers such as wool and silk. Synthetic fibers may include polyethylene terephthalate (PET), polyolefin, polyamide 6, polyamide 6,6, polylactic acid (PLA) fibers, viscose rayon, acrylic, or other fiber types, such a flame-resistant fibers as needed. Suitable thermoplastic synthetic staple fibers may be mono-component or bi-component type fibers. A variety of yarn spinning types can be used, such as ring spun, open end, air-jet, compact spinning, and the like. Continuous filaments yarn may include either or both mono-component or bicomponent filament types. Continuous filament yarns can be polyethylene terephthalate, polyolefin, and/or polyamide 6, polyamide 6,6, polylactic acid filaments. All of which may be dyed with lignin.

In a woven fabric example, any type of woven construction could be used, such as a plain weave, twill weave, satin/sateen, twill, basket weave, oxford, basket weave, rib weave, or any other suitable woven construction. Woven fabrics may include synthetic yarns, natural yarns or blended yarns, single end yarns, or plied yarns. The yarns for a woven fabric can use yarns with a range of yarn counts suitable for garments or accessories may be in a range of 6 Ne to 120 Ne. If continuous multifilament yarns form the garment panel, the count range may be in a range of 10 denier to 250 denier.

A twill fabric weave is made by passing the weft thread over one or more warp threads than under two or more warp threads and so on, with an offset between rows to create a pattern. Twill weaves are often designated as fractions, such as 2/1, 3/1, 4/1, where the numerator represents the number of warp strings and the denominator the number of weft yarn. This results in a fabric that has a front side (“technical face”) and a back side (“technical back”). When lignin dyed yarn is used as the warp yarn and the weft yarn is white, the technical face will have a predominantly brown color while the technical back will have a predominantly white color.

In another example, fabric is a knit fabric. Knit fabrics may be a weft knits, such as single jersey knit fabric, a double knit, rib knit, or any other type of weft knitted fabric. The knit fabrics may have a combination of knit constructions to improve edge stability and maintain flexibility. The knit fabric may alternatively be a warp knit, such as a tricot or Rachel warp knitted fabric. Yarns used in the knit fabric, whether weft knit or warp knits, can have a range of yarn counts. For instance, knit yarns can have a count in a range between 6 Ne to 120 Ne or the equivalent denier if continuous filaments are used.

In some processes, yarn is dyed within lignin and then woven into a fabric. In other processes the yarn may be woven into a fabric, such as through a twill weave, and the constructed fabric is dyed, e.g., in a dye bath described above. In yet still other processes, fibers are dyed with lignin which are in turn spun into lignin-dyed yarn and then woven into lignin-dyed fabric. In some examples, the fabric is composed of at least 40 percent cellulosic material. In preferred embodiments, the fabric is composed of at least 30 percent cellulosic material.

As discussed herein, fabric and/or yarns may be passed through a dye bath with lignin present in amounts of 10 weight percent to 30 weight. percent in solution. In trials, the lignin dye pickup was observed to be in a range of 90 percent to 100 percent by weight in each trial. The fabric and/or yarns may be passed through a dye bath in a single dip or multiple dips. A desired shade of brown may be achieved by dipping the substrate (fiber, yarn, fabric, garment) within a dye bath and varying the concentration of lignin dye in the dye-bath solution, the lignin dye used, and increasing or decrease the number of times the substrate is dipped. For example, multiple dips at a higher concentration may yield a more saturated lignin dye color versus a single dip at lower concentrations.

Typically, the dipping process of the dye bath provides a yarn and/or fabric that contains from 0.3 weight percent to 10 weight percent of lignin dye. The weight percent of lignin in the fabric is dependent on the dye uptake, concentration of dye in the bath, the number of dips experienced as well as the fabric construction. In some further embodiments, the fabric and/or yarn contains from 0.3 weight percent to 5 weight percent of lignin dye. As a non-limiting example, a pair of denim jeans that may weigh from 0.34 kg to 0.45 kg may exhibit a brown color having a range of 2 grams to 15 grams of lignin distributed throughout. Furthermore, it is to be appreciated that for a woven fabric, the product may be a combination of lignin-dyed yarns and other yarns. In the case of a twill fabric, e.g., denim, the lignin-dyed yarns may be the warp yarns while the weft yarn may be composed of a non-lignin dyed yarn (white yarns, synthetic yarns, etc.)

The presence of lignin in the above quantities may be sufficient to impart to the fabric the natural bacteriostatic and anti-fungal properties of lignin. That is, the presence of lignin may help prevent the growth of certain bacteria and/or undesirable fungi.

While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Any combination of the above embodiments is also envisioned and is within the scope of the appended claims. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope of the claims appended hereto. 

What is claimed:
 1. A yarn comprising: a plurality of fibers comprising lignin as a primary dye agent.
 2. A textile fabric comprising: a plurality of yarns according to claim
 1. 3. A garment comprising: a plurality of yarns according to claim
 1. 4. The yarn according to claim 1, wherein the plurality of fibers comprise lignin in a range of 0.3 percent to 10 percent by weight.
 5. The yarn according to claim 1, wherein the plurality of fibers comprise lignin in a range of 0.3 percent to 5 percent by weight.
 6. The yarn according to claim 1, wherein the plurality of fibers include at least 30 percent cellulosic fibers.
 7. The yarn according to claim 1, wherein the plurality of fibers comprise at least 30 percent cellulosic fibers.
 8. The yarn according to claim 1, wherein the plurality of fibers are bacteriostatic.
 9. A textile fabric comprising: a fiber-based material including lignin as a primary dye agent.
 10. The fabric according to claim 9, wherein the fiber-based material includes lignin in a range from 0.3 percent to 10 percent by weight.
 11. The fabric according to claim 9, wherein the fiber-based material includes lignin in a range from 0.3 percent to 5 percent by weight.
 12. The fabric according to claim 9, wherein the fiber-based material comprises at least 30% cellulosic fibers.
 13. The fabric according to claim 9, wherein the fiber-based material is bacteriostatic.
 14. The fabric according to claim 9, wherein the fiber-based material comprises a first fiber-based yarn and a second fiber-based yarn, the first fiber-based yarn including lignin as a primary dye agent, the first fiber-based yarn is a warp yarn or a weft yarn and the second fiber-based yarn is the other of a warp yarn or a weft yarn, the first fiber-based yarn and the second fiber based yarn woven in a twill pattern.
 15. The fabric according to claim 14, wherein the second fiber-based yarn comprises lignin as a primary dye agent.
 16. A brown colored garment comprising: a fiber-based material including lignin as a primary dye agent.
 17. The garment according to claim 16, wherein the fiber-based material comprises lignin in a range of 0.3 percent to 10 percent by weight.
 18. The garment according to claim 16, wherein the fiber-based material comprises lignin in a range of 0.3 percent to 5 percent by weight.
 19. The garment according to claim 16, wherein the fiber-based material is at least 30 percent cellulosic fibers.
 20. The garment according to claim 16, wherein the fiber-based material comprises a first fiber-based yarn and a second yarn, the first fiber-based yarn comprises lignin as a primary dye agent. 